Step-by-step explanation:
The easy way
the Light Dependent reactions and the Calvin Cycle
Or the hard way
Photosynthesis can be divided into two sets of reactions - the Light Dependent reactions and the Calvin Cycle (also known as the light independent reactions. In the Light Dependent reactions, light energy is absorbed by photosynthetic pigments and used to produce the products ATP & NADPH which are required for the Calvin Cycle (light dependent reactions) which generates a pre-cursor of sugar. Water is also split in the light dependent reactions, giving off the by-product oxygen and carbon dioxide is required for the Calvin Cycle in order to produce the pre-cursor of sugar.
6CO2 + 6H2O ---> C6H12O6 + 6O2